Chimney cowls and ventilating devices



June 20, 1961 c. E. BREWER 2,988,982

CHIMNEY COWLS AND VENTILATING DEVICES Filed Sept. 2, 1958 i gwfiwmwox.

Clifford Ed amdf/ ewen .IBY

ATTORNEYS Sims PM? ing devices, firg. to cowls of the type suitably shaped to create a reducedpressure in the chimney flue or air duct, together means to facilitate the fixing of the cowl to the chimney pot or air duct outlet. Such a construction. embodies a top cover plate, to the edges of which are equidistant-1y attached at right angles, or thereabouts, four curvedor the like plates, each suitably dimensioned ze tah i ha qn wd na apert re b t ee the adjacent VerticaLedgesofthe said plates. The apertures are separately bridged at their base by an angle plate or bracket, each of which accommodates a bolt, in a manner that each bolt .cotacts with its respective clip or lug, which is ptovided' inzo'r on .the peripheral wall of ,a vertically .disposed cylindrical or suitably shaped sleeve. The lower part of the sleeve is adapted for co-axial relationship upon or within the chimney pot or air duct outlet, and its upper portion is housed in co-axial relationship within the open ended base of the said cowling, in a manner to establish an annular space between the sleeve and the cowling.

No doubt it is recognised by all who have tackled the problem in designing a cowl for the prevention of down draught, that, having successfully overcome the latter, there still looms up other problems. For instance, to quote but four of these:

Firstly, the amplification of the sound of wind passing onto and/or through the cowl head, which is a source of annoyance to the occupants of the room to which the chimney flue or vent is attached.

Secondly, the difficulty in fixing a cowl to a chimney pot which has no outwardly directed beading or flange at its uppermost part.

Thirdly, where the architectural feature of a chimney stack does not show an exposed flue rim to which a cowl might be wired.

Fourthly, the time lost to the builder (or user) in ascertaining the internal diameter of the chimney pot or vent before obtaining a cowl or a terminal for same. Over an extensive period, calculated methods have been put to practice by me of various prototype cowls, adapted to chimneys on marine site locations, where extreme weather conditions prevaiLThe outcome of such research is the subject matter of this invention.

In order that the invention may be clearly understood, and readily carried into effect, reference is directed to the accompanying drawings, wherein:

FIG. 1 is a side elevational view of the cowl or ventilating device, according to the invention.

FIG. 2 is a sectional view of FIG. 1 on the line A/A.

FIG. 3 is a sectional view of FIG. 1 on the line B/B.

FIG. 4 is a plan view of the top cover plate of FIG. 1.

FIG. 5 is a sectional view similar to that of FIG. 3 and showing an alternative form. of construction, and

FIG. 6 is a sectional vertical view of the cowl showing the sleeve extended upwardly, and with apertures therein.

The use of sheet metal is assumed in the preferred construction to which I now refer, in which FIGS. 1, 2 and 4, show the top cover plate 1, to which is attached at right angles, or thereabouts, four curved side plates 2, each providing a transversely concave external surface and all of a dimension to suitably establish a longitudinal aperture 3, between the adjacent vertical edges -This invention relates to chimney cowlsgand ventilat-' 4, of the said curved plates, each aperture 3, is securely bridged at its base by a bracket 5 secured to the adjacent edges 4 as by welding, each of which brackets is apertured to receive a bolt 6. The bolts are formed with a winged type head for the purpose of dispensing with the need for a tool to manipulate same.

equidistantly located around the peripheral wall of a vertically disposed sleeve 8 and secured thereto as .by welding and threaded apertures extend through each lug and the peripheral wall to receive the threaded ends of the bolts 6. The lower part of the sleeve 8, is adapted as shown in FIG. 2, to be engaged in the upper end of, a chimney pot 9 in closely fitting relation therewith, while the upper portion of the said sleeve is shrouded in co-axial relationship by the aforesaid cowling, 'thus establishing an annular space 10 between the inner surfaces of the side plates and the-said sleeve.

Provision is made for securely holding the cowl unit to the chimney pot, or air duct outlet, by furnishing each bolt 6, with a gripping element in the form ofa suitably, shaped clip 11, and a locking nut 12, it being understood that the clip 11 may be adjusted to its desired locking position along the bolt 6, and securely held thereto by the lock nut 12 so that the chimney pot or air duct outlet is gripped between the sleeve 8 and the clips 11.

FIG. 5 illustrates an alternative manner of securing the plates 2 to the sleeve 8 by means of bolts 6a extending through each plate 2 at the centre thereof and threadingly engaging in lugs 7a suitably positioned on the sleeve 8 and secured thereto as by welding. The brackets 5 are retained in the alternative construction of FIG. 5 and serve to maintain the edges 4 in aligned spaced relation.

Preferably the top cover plate will be shaped with upswept portions 13, as shown in FIGS. 1 and 2 of the drawings. FIG. 4 of the drawings indicates the locations 14, where the upward trend of these upswept portions 13 commences. The upper edge surfaces of the side plates 2 are then formed with upwardly inclined end portions to mate with the upswept portions 13 and enable the plates to be welded to the top cover plate.

When the construction is adapted as a terminal to an air duct outlet, and where such outlet is horizontally disposed, it is preferable that the top cover plate 1,

should obtain a flat or domed formation instead of the upswept contours 13, as described.

It will be understood that the stiffening or strengthening of the sheet metal parts may be carried out by the usual and known methods, also the formations of the top cover plate will provide for the draining oif of water or snow.

It is further anticipated that when the foregoing features are embodied in a construction for use as a terminal to an air duct outlet, the sleeve 8, will be dimensioned to suitably extend its upper portion to make contact, or thereabouts, with the inside of the top cover plate 1, and that suitably shaped apertures 15 will be provided in the peripheral wall of the said sleeve 8, as shown in FIG. 6 in which it will be seen that the apertures 15 are non-coincident with the longitudinal apertures 3 to prevent direct communication between the air duct and the aperture 3.

One of the primary objects of this invention is to divert heavy foggy atmospheric pressures (now more commonly known as smog) clear of the open upper end of the flue or ventilating duct. Distinctively coloured smoke used in tests during heavy smoggy atmospheric conditions, was found to be leaving the cowl, more particularly in the paths as shown by the arrows C and D in FIG. 2: That is to say in a downward V Patented June 20, 1961 The thread. end of each bolt co-acts with a lug 7, four of which aretrend via the lower area of the aperture 3, and the annular space 10, whilst also the fire burned more clearly and freely than when the cowl was later removed from the chimney pot during such said conditions.

What I claim is:

1. A chimney cowl for attachment to a chimney pot or the like comprising a sleeve member, a first portion of said sleeve member for engaging in the upper end of a chimney pot in closely fitting relation therewith, a second portion of said sleeve member adapted to extend upwardly from the said upper end of the chimney pot when the said first sleeve portion is engaged therein, a top cover plate, a plurality of side plates extending downwardly from the cover plate to surround the said second sleeve portion, said cover plate having edges coextensive with and secured to the upper edges of the side lates, means connecting the said side plates to the second sleeve portion in spaced relation therewith whereby the side plates support the top cover plate vertically above and spaced a substantial distance from the upper end of the sleeve member, the said side plates being transversely curved to provide horizontally concave exterior surfaces having their respective vertical edges spaced one from another, elongated vertically extending apertures formed by adjacent vertical edge portions of the side plates, the upper edge of each of said side plates being inclined outwardly and upwardly to the vertical edge portions thereof, said cover plates being formed with upswept portions that mate with the inclined upper edges of the side plates and define the upper edge of the vertical extending apertures, and an annular opening formed between the bottom edge portions of the side plates and the sleeve member.

2. A chimney cowl as claimed in claim 1 in which the said connecting means includes adjustable gripping elements for engaging the outer periphery of the upper end portion of the chimney pot whereby the upper end of the chimney pot is gripped between the sleeve member and the said gripping elements to secure the cowl to the chimney pot.

References Cited in the file of this patent UNITED STATES PATENTS 526,939 Peel Oct. 2, 1894 2,522,995 Coleman Sept. 19, 1950 2,582,905 Harmon Jan. 15, 1952 2,805,616 Roth Sept. 10, 1957 2,878,745 Niblett Mar. 24, 1959 FOREIGN PATENTS 609,741 Great Britain Oct. 6, 1948 144,680 Australia Jan. 7, 1952 

